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Off-road 차량용 디젤엔진의 NOx 저감을 위한 EGR 시스템 적용에 관한 연구
강정호(Jeongho Kang),남대우(Daewoo-Nam),정건우(Gunwoo Jeong),조규백(Kyubak Cho),장용수(Youngsoo Jang),김문형(Munhyung Kim),박상호(Sangho Park) 한국자동차공학회 2010 한국자동차공학회 부문종합 학술대회 Vol.2010 No.5
In order to decrease NOx emission, the EGR system was applied on the off-road vehicle diesel engine. First of all, the primary map of EGR rate was formed by testing EGR in various engine driving conditions, and the engine performance and the NOx reduction was investigated. As the results of experiments, in the case of applying HPL EGR system on diesel engine used WGT, it is shown that the operating region of EGR is effective in low or middle load due to changing the differential pressure between turbocharger inlet and intake manifold. Increased EGR rate, NOx emission decrease according to increasing EGR rate, but THC shows the increasing tendency because of the increased fuel mass to compensate for the deteriorated power by EGR. Also, the temperature in intake and EGR system is raised highly by increasing the recirculated exhaust gas. From above results, the operating region of EGR is limited. However, NOx emission entirely decrease about 20~40% by applying EGR. So, if using the appropiate EGR rate for various engine driving condition, it is expected that NOx reduction is improved more and more.
CNG 엔진에서 직접분사와 포트분사에 따른 연소특성 비교
강정호(Jeongho Kang),최성우(Sungwoo Choi),김진영(Jinyoung Kim),염정국(Jeongkuk Yeom),정성식(Sungsik Chung),하종률(Jongyul Ha) 한국자동차공학회 2004 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-
CNG is one of the most promising alternative fuels because of lower exhaust emissions and lower CO2 emission with high thermal efficiency. However, as CNG has a low volumetric efficiency due to a gaseous charge and increasing time loss due to low burning velocity as compared with gasoline, the brake horse power is reduced. To solve these problems, the PFI CNG engine was modified to the DI CNG engine which directly supplies natural gas in the combustion chamber. And we investigated the combustion characteristics of the DI CNG engine by means of cylinder pressure, combustion duration and cycle variation etc. As a result, the Dl CNG engine shows better volumetric efficiency and shorter overall combustion duration than the PFI CNG engine.
직접분사식 CNG 엔진에서 연료공급 조건이 연소에 미치는 영향
강정호(Jeongho Kang),염정국(Jeongkuk Yeom),정성식(Sungsik Chung),하종률(Jongyul Ha) 한국자동차공학회 2005 한국자동차공학회 지부 학술대회 논문집 Vol.- No.-
CNG fuel is one of the most promising alternative fuels because of lower exhaust emissions and lower CO2 emission with high thermal efficiency. However, the brake horse power is reduced because a CNG fuel has a low volumetric efficiency due to the gaseous charge and increase in time loss with lower burning speed as compared with gasoline fuel. To solve these problems, the DI Diesel Engine was modified to the DI CNG Engine which directly supplies natural gas into the engine cylinder. The combustion characteristics of the Dl CNG engine such as cylinder pressure, cycle variation, combustion duration and emissions were investigated in this study. Consequently, it could be verified that the volumetric efficiency, overall combustion duration and lean limit were improved by using DI technique in the CNG Engine.
직분식 CNG 엔진에서 연료공급 조건이 연소와 출력 특성에 미치는 영향
강정호(Jeongho Kang),염정국(Jeongkuk Yeom),정성식(Sungsik Chung),하종률(Jongyul Ha) 한국자동차공학회 2005 한국자동차공학회 춘 추계 학술대회 논문집 Vol.2005 No.11_1
A CNG fuel is one of the most promising alternative fuels because of lower exhaust emissions and lower CO₂ emission with high thermal efficiency. However, the brake horse power is reduced because a CNG fuel has a low volumetric efficiency due to the gaseous charge and increase in time losses with lower burning speed as compared with gasoline fuel. To solve these problems, the DI Diesel Engine was modified to the DI CNG engine which a spark plug was mounted on the engine cylinder head. The purpose of this study is to investigate the effect of different injection conditions (early injection mode, late injection mode) on combustion and performance in the DI CNG engine. The combustion characteristics of the DI CNG engine such as in-cylinder pressure, cycle variation, combustion duration and emissions were investigated in this study. The results show that late injection timing during the compression stroke significantly extended lean limit in the low load. Consequently, it could be verified that the overall combustion duration and lean limit were improved by using the variation of injection timing and the stratification was controlled by injection timing in the DI CNG engine.
강정호(Jeongho Kang),정재우(Jaewoo Chung),강우(Woo Kang),김남호(Namho Kim) 한국자동차공학회 2006 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-
In order to increase the practicality of the DME engine, studies are being performed on the 4-cylinder engine, and various control devices and prototype engines have been made or improved for testing. Through such various tests and equipment improvement, the problems related to the engines made by KATECH are materialized and the engine performance improvements are being implemented. First, before making the prototype engine, this study performed the engine performance test by independently running the 4-cylinder engine with the fuel supply system separated. Of the test results, the effect by the forced charging was presented. Various problems are required to be improved, which were presented through this preliminary test and were listed and reflected for the manufacture of the prototype engine.
강정호(Jeongho Kang),정재우(Jaewoo Chung),김남호(Namho Kim),정수진(SooJin Jeong),김병수(ByoungSoo Kim),강우(Woo Kang) 한국자동차공학회 2008 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-
In Korea Automotive Technology Institute(KATECH), in order to increase the practicality of the DME engine and vehicle. it is performed that the improvement of DME common rail engine system with developments of fuel supply systems. From full load tests of a proto DME engine, various engine performances are compared with performances of a base Diesel engine. In this paper, it is briefly introduced that engine system and fuel supply systems of DME engine and full load engine test results From tests results, BSFC and torque performance has lower performance at high engine speed conditions compared with Diesel engine performances. But the ability of DME as an alternative fuel in turbochargerd commonrail Diesel engine could be experimentally confirmed.